https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110838
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Known to work| |14.0
--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed on trunk. I think the issue is present on the branches as well in that
we generate
vect_patt_48.21_145 = VIEW_CONVERT_EXPR<vector(8) signed
short>(vect_patt_49.20_143);
vect_patt_48.21_146 = VIEW_CONVERT_EXPR<vector(8) signed
short>(vect_patt_49.20_144);
vect_patt_46.22_147 = vect_patt_48.21_145 >> 31;
vect_patt_46.22_148 = vect_patt_48.21_146 >> 31;
and
psraw $31, %xmm3
psraw $31, %xmm2
so we have out-of-bound arithmetic vector shifts here which might or might
not cause issues on other targets than x86. psraw documents
"If the value specified by the count operand is greater than 15 (for words)
[...], each destination data element is fille with the initial value of
the sign bit of the element." which is what we intended to compute.
